At a railway station in Hyderabad, India, rescued child laborers stand in a queue to board a train to be reunited with their parents in Bihar, one of India's poorest states, Feb. 5, 2015. Police have rescued hundreds of children working in hazardous industries in the southern Indian city despite laws that ban child labor.

Chennai, India — After performing at one of India's top arts centers in the city of Chennai, folk musician N Deepan stunned the audience when he took the microphone and spoke about being a child laborer.

From the age of 10, he said he had been in and out of school, spending most of his time toiling at construction sites or binding books in stores.

And then he discovered the parai, one of the oldest traditional drums used in the southern Indian state of Tamil Nadu.

"We went back to school, we played music in the evenings and all of us eventually made it to college."

India is home to 5.7 million child workers aged between five and 17, according to the International Labor Organization, which estimates there are 168 million child workers globally.

More than half of India's child workers labor in the fields, and over a quarter in manufacturing – from embroidering clothes to weaving carpets and making matchsticks. Children also work in restaurants and hotels, and as domestic workers.

The artists in Monday's show, who formed Nanbaragal Gramiya Kalaikal (Friends of Folk Art) in 2013, grew up in the slums of north Chennai, where it was normal for children to work until just a few years ago.

The revelation that the musicians were once child laborers astonished the audience attending the arts festival at Kalakshetra, a leading cultural institution which promotes the classical arts including the prestigious Bharatnatyam dance form that originated in Hindu temples.

"We use every platform we can to talk about our past," Deepan told the Thomson Reuters Foundation before the show.

"In spaces like this, considered sacred by dancers, the reality of life in another part of the city including the slums I grew up in should be reflected."

Most of the performers, who all dance while drumming, were rescued and persuaded to go back to school by members of the nonprofit organization Arunodhaya – a center for street and working children.

"We all worked. When I was 12, I went on the fishing boats," said performer S Pavithran.

"I dropped out of school and spent the entire day loading and unloading baskets of fish. Now I am doing my masters in business administration and also have a part-time job."

The number of working children in Chennai's slums has fallen recently following awareness programs and interventions by civil society groups and the government. The drummers have also become an inspiration for families in the area.

"We know how easy it is to drop out so if we find any child wandering around during school hours, we literally drag him or her back to school. Today, even their parents are grateful when we do it," Deepan said.

The folk group, a mix of men and women, performs in schools and at weddings as well as in shows – and at the end of most performances they tell the story of their childhood.

They are also eager to dispel misperceptions about the parai – a flat portable drum.

"The parai drummers are most often considered illiterate and associated with playing at funerals," Deepan told the audience.

"We are all educated and we are not at a funeral today. The parai gave us freedom and a purpose."